spi: add a method for configuring CS timing (f1ca9992) · Commits · 戴 / test

drivers/spi/spi.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -2995,6 +2995,21 @@ int spi_setup(struct spi_device *spi)
		}
		EXPORT_SYMBOL_GPL(spi_setup);

		/**
		* spi_set_cs_timing - configure CS setup, hold, and inactive delays
		* @spi: the device that requires specific CS timing configuration
		* @setup: CS setup time in terms of clock count
		* @hold: CS hold time in terms of clock count
		* @inactive_dly: CS inactive delay between transfers in terms of clock count
		*/
		void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold,
		u8 inactive_dly)
		{
		if (spi->controller->set_cs_timing)
		spi->controller->set_cs_timing(spi, setup, hold, inactive_dly);
		}
		EXPORT_SYMBOL_GPL(spi_set_cs_timing);

		static int __spi_validate(struct spi_device spi, struct spi_message message)
		{
		struct spi_controller *ctlr = spi->controller;

include/linux/spi/spi.h

+15 −0

Original line number	Diff line number	Diff line
		@@ -330,6 +330,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
		* must fail if an unrecognized or unsupported mode is requested.
		* It's always safe to call this unless transfers are pending on
		* the device whose settings are being modified.
		* @set_cs_timing: optional hook for SPI devices to request SPI master
		* controller for configuring specific CS setup time, hold time and inactive
		* delay interms of clock counts
		* @transfer: adds a message to the controller's transfer queue.
		* @cleanup: frees controller-specific state
		* @can_dma: determine whether this controller supports DMA
		@@ -363,6 +366,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
		* @unprepare_transfer_hardware: there are currently no more messages on the
		* queue so the subsystem notifies the driver that it may relax the
		* hardware by issuing this call
		*
		* @set_cs: set the logic level of the chip select line. May be called
		* from interrupt context.
		* @prepare_message: set up the controller to transfer a single message,
		@@ -488,6 +492,17 @@ struct spi_controller {
		*/
		int (setup)(struct spi_device spi);

		/*
		* set_cs_timing() method is for SPI controllers that supports
		* configuring CS timing.
		*
		* This hook allows SPI client drivers to request SPI controllers
		* to configure specific CS timing through spi_set_cs_timing() after
		* spi_setup().
		*/
		void (set_cs_timing)(struct spi_device spi, u8 setup_clk_cycles,
		u8 hold_clk_cycles, u8 inactive_clk_cycles);

		/* bidirectional bulk transfers
		*
		* + The transfer() method may not sleep; its main role is

Admin message